The waters of the Earth’s oceans are for the most part in liquid form. What happens when you take a half full bottle of water and shake it up? Do you see the bubbles swirling rapidly around inside the water bottle? While liquid water molecules do generally attract one another forming a body of water, molecules within that body of water are free to move about, becoming thoroughly mixed up.

The waters of the Earth’s oceans can be mixed up by a number of forces, including wind, splashing against a rocky shore, swimmers, boats, etc. However, the items mentioned above create only a very minimal amount of mixing. Three important forces create a much more prevalent mixing of the ocean’s waters, causing the water to move about from one place to another, as though a giant were shaking them in the same manner that you shake a water bottle.